UREDINALES OF GUATEMALA 
333 
nate within the epidermal cells, which they stimulate into abnormal 
growth. When the overarching part of the host is pushed back from 
the sorus, only the outer wall or upper half of the epidermal layer is 
involved. The species, on account of its one-celled tehospores, is 
often listed as Uromyces Rtihi Diet. & Holw\ 
The genus Spirechina is here placed in the Uredinaceae (Melamp- 
soraceae) in association with Kuehneola. It has usually been placed 
near Phragmidium, because of its host affinities and the subcuticular 
pycnia, but both of these characters ally it equally well to Puccinias- 
trum. The occasional formation of intracellular urediniospores and 
teliospores also shows relationship to that genus. The lack of a 
uredinial peridium, however, places it, together with Kuehneola, in 
the subfamily Uredinatae, rather than in the Pucciniastratae. 
The species was collected by Kellerman, on Ruhiis glaucus Benth., 
Guatemala City, Feb. 12, 1905, II, 4625; between Antigua and Volcan 
de Agua, Feb. 15, 1905, II, III, 5321; same, Feb. 18, 1905, II, iii, 5319, 
and II, 5320; on R. poliophylhis Focke, Volcan de Atitlan, Dept. 
Solola, Feb. 16, 1906, II, III, 5415; same between Antigua and Volcan 
de Agua, Feb. 18, 1905, II, 5363, all being reported by Kern in My- 
cologia. Numbers 462^ and 5J^5j were first erroneously reported by 
Kern in Journ. Myc, /. c, as Knelweola albida, a species not yet known 
south of the United States. 
13. Spirechina Arthuri (Syd.) Arth. (on Rosaceae). 
Riihus guyanensis Focke (?), Road between Quezaltenango and 
Colomba, Feb. 4, 1917, O, IIi, II2, iii, 832. 
This collection gives the first opportunity to study pycnia and 
uredinia of the species. Heretofore only a few urediniospores have 
been seen in connection with teliospores, independent uredinia not 
having been found. 
The pycnia are amphigenous, scattered on gall-like swellings of 
the leaf, 0.2-1.5 cm. in diameter. They are subcuticular, golden- to 
chestnut-brown, discoid, 190-480/i broad by 48-80/x high; pycnio- 
spores ellipsoid, colorless, 3-4 long. 
The primary uredinia are on the pycnial galls, at first circinating, 
afterward becoming crow^ded, confluent, and covering the gall. The 
urediniospores are 16-23 by 30-42 /x, with the walls colorless, about i/i 
thick, thickened at the apex 7-1 8^^, and the apex rounded or acute. 
The secondary uredinia are not on galls, but are scattered over the 
under surface of the leaf, round, 0.1-0.2 mm. across, pulverulent, 
yellow fading to white, with the ruptured epidermis inconspicuous. 
